Project description:Purpose: We characterized the role of EKLF in erythroblast island macrophages in E13.5 mouse fetal liver by analysing the transcriptomes of F4/80+ macrophages from WT and EKLF-/- by RNA-Seq. In addition we analyzed the transcriptomes of F4/80+ fetal liver macrophages from an EKLF/GFP mouse, where GFP acts as a surrogate for EKLF expression, to determine the genes enriched in EKLF/GFP+ macrophages compared to EKLF/GFP- macrophages where EKLF is not expressed. Finally, we used single cell RNA sequencing to resolve the heterogeneous population of F4/80+ macrophages from WT. Methods: For RNA-Seq from WT and EKLF-/- F4/80+ macrophages were FACS sorted from primary E13.5 mouse fetal livers and RNA was isolated using the Trizol method. F4/80+ macrophages were also FACS sorted from the EKLF/GFP mouse and the GFP+ and GFP- populations were collected. The GFP+ population had low cell numbers and therefore RNA was isolated using an Agilent RNA Nanoprep kit. For single cell sequencing, E13.5 fetal livers were stained with F4/80-PE antibody and the F4/80-PE+ cells were purified using an EZ-Sep PE selection kit (mouse). 25,000 cells were submitted for single cell sequencing for the Chromium V3 platform. Library preparation was done using the standard Illumina Truseq workflow, and libraries were sequenced in a Hiseq 2500 for WT and EKLF-/-, or Novaseq for EKLF/GFP and single cell sequencing. Results: We found that 1954 genes are differentially expressed in EKLF-/- F4/80+ macrophages vs WT and 2330 genes are differentially enriched in EKLF/GFP+ F4/80+ macrophages using DESeq2. Of these, 504 are common and constitute the EKLF-dependent gene expression program in F4/80+ fetal liver macrophages. We resolved the F4/80+ WT macrophages into 13 clusters based on gene expression and find that 23% of the total F4/80+ cells express EKLF. Conclusions: We find that the F4/80+ fetal liver macrophage are a unique cell type. We identify the EKLF-dependent gene expression program in these macrophages and determine an important transcription circuit governed by EKLF that constitute cell cycle and other Klf and Sp family transcription factors. Single cell sequencing showed a highly heterogeneous population of macrophages with activated macrophage as well as erythro-myeloid characteristics. Based on the expression of EKLF, we identified specific cell surface markers for EKLF+ F4/80+ macrophages.
Project description:F4/80+ macrophages treated with TGFb2 are potently tolerogenic. Our understanding of the molecular mechanisms mediating the development of these tolerogenic properties is incomplete. We used microarray analysis to identify molecules that are involved in the tolerogenic mechanisms in murine TGFb-treated macrophages. Thioglycolate-elicited peritoneal exudate cells (F4/80+ macrophages) were treated with either PBS or TGFb2 overnight then total RNA extracted and subjected to microarray analysis.
Project description:Genes expression in Ly6C+/F4/80+ inflammatory macrophages, CX3CR1+/F4/80+ tissue resident macrophages and Ly6G+/F4/80- neutrophils which were isolated from day 3 wounds in C57/B6 mice aged 8 weeks by cell sorting
Project description:RNAseq was performed on PoEMs (CD11b+, F4/80+, PDPN+) vs. non-PoEMs (CD11b+, F4/80+, PDPN-) sorted from orthotopically inoculated 4T1 tumors in WT mice.
Project description:Genes expression in Ly6C+/F4/80+ inflammatory macrophages, CX3CR1+/F4/80+ tissue resident macrophages and Ly6G+/F4/80- neutrophils which were isolated from day 3 wounds in C57/B6 mice aged 8 weeks by cell sorting Ly6C+ macrophages expressed higher (over 5 folds) levels of 241 genes compared to CX3CR1+ macrophages, and 3382 genes compared to neutrophils
Project description:F4/80+ macrophages treated with TGFb2 are potently tolerogenic. Our understanding of the molecular mechanisms mediating the development of these tolerogenic properties is incomplete. We used microarray analysis to identify molecules that are involved in the tolerogenic mechanisms in murine TGFb-treated macrophages.
Project description:Dendritic cells (DCs) and macrophages (MPs) are important for immunological homeostasis in the colon. We found that F4/80hi CX3CR1hi (CD11b+CD103-) cells account for 80% of mouse colonic lamina propria (cLP) MHC-IIhi cells. Both CD11c+ and CD11c- cells within this population were identified as MPs based on multiple criteria, including a MP transcriptome revealed by microarray analysis. These MPs constitutively released high levels of IL-10 at least partially in response to the microbiota via an MyD88-independent mechanism. In contrast, cells expressing low to intermediate levels of F4/80 and CX3CR1 were identified as DCs, based on phenotypic and functional analysis and comprise three separate CD11chi cell populations: CD103+CX3CR1-CD11b- DCs, CD103+CX3CR1-CD11b+ DCs and CD103-CX3CR1intCD11b+ DCs. In non-inflammatory conditions, Ly6Chi monocytes differentiated primarily into CD11c+, but not CD11c- MPs. In contrast, during colitis, Ly6Chi monocytes massively invaded the colon and differentiated into pro-inflammatory CD103-CX3CR1intCD11b+ DCs, which produced high levels of IL-12, IL-23, iNOS and TNF. These findings demonstrate the dual capacity of Ly6Chi blood monocytes to differentiate into either regulatory MPs or inflammatory DCs in the colon, and that the balance of these immunologically antagonistic cell types is dictated by microenvironmental conditions. FACS sorted expression from normal controls
Project description:Melanomas display high numbers of tumor-associated macrophages (TAMs), which correlate with worse prognosis but also retain the potential to restore anti-tumor activity. Harnessing macrophages for therapeutic purposes has been particularly challenging due to their heterogeneity, based on their ontogeny and function and driven by the tissue-specific niche. In the present study, we used the YUMM1.7 murine melanoma model to better understand melanoma TAM origin and dynamics during tumor progression, with potential therapeutic implications. We identified distinct TAM subsets based on F4/80 expression, with the F4/80high fraction increasing over time and displaying tissue-resident-like phenotype. While skin-resident macrophages showed mixed ontogeny, F4/80+ TAM subsets in i.d. YUMM1.7 tumors originated almost exclusively from bone-marrow precursors. Multiparametric analysis of macrophage phenotype showed a temporal divergence of F4/80+ TAM subpopulations, which also differed from skin-resident subsets, and from their monocytic precursors. Overall, F4/80+ TAMs displayed co-expression of M1- and M2-like canonical markers, and RNA-seq and pathway analysis showed differential immunosuppressive and metabolic profiles. GSEA showed F4/80high TAMs to rely on oxidative phosphorylation, with increased proliferation and protein secretion while F4/80low cells had high pro-inflammatory and intracellular signaling pathways, with lipid and polyamine metabolism. Overall, the present in-depth characterization provides further evidence of the ontogeny of the evolving melanoma TAMs. Some of these gene profiles matched recently-identified TAM clusters in other tumor models and human cancers, which in turn can lead to more effective therapies targeting specific immunosuppressive cells in advanced tumor stages.
Project description:RNA-sequencing was performed on sorted tumor-associated macrophages (CD45+7AAD-CD11b+F4/80+CD8-Ly6C-Ly6G-) from 4T1 tumor (murine breast cancer) bearig mice with or without JHU083, pro-drug of 6-Diazo-5-oxo-L-norleucine (glutamine antagonist) treatment for expression profiling